The performance of two commercial static mixers in the laminar creeping flow regime, the Kenics mixer (Chemineer) and the SMX mixer (Koch Engineering), are compared using 3D numerical simulations. Several criteria are chosen as the basis for the performance evaluation, namely, the pressure drop, the mixer length, the Lyapnnov exponent, the mean shear rate and the intensity of segregation. It appears that the SMX mixer is more efficient than the Kenics mixer to achieve a difficult mixing task or when installation space is restricted.